ATHENS — Rena Dourou, the new prefect of Athens and a member of the left-wing Syriza Party, was taking stock of the cavernous office she inherited recently, making plans to move to a cheaper and more functional alternative.

“Look at this place,” she said. “It will take me until Monday just to get from my desk to the door. And downstairs, you should see the space people are working in. I am not saying this because I am leftist. People need space to do proper work.”

The polls these days show that Alexis Tsipras, the leader of Syriza, just a marginal party until the economic crisis, may be poised for a victory in the next national elections, ending the lock that two parties have had on the government for more than four decades.

But for the time being, Ms. Dourou’s election as prefect, the rough equivalent of the governor of New York, represents the party’s biggest victory so far.

Petite and blond, Ms. Dourou ran an American-style campaign, going door to door, something most Greek politicians avoid out of fear of being assaulted by angry citizens. On her office wall, she kept a map of the region with dozens of pins indicating where she had traveled. Few opinion polls correctly predicted her victory.

But she brought her handshakes and her motto — “if you feel you have the life you deserve, don’t do anything and vote for the same old people” — all over the city, even to areas considered bastions of the right-wing Golden Dawn party.

“I don’t know whether it got me any votes,” she said. “But people were amazed to see me. They had never met a politician. They were touching me, saying, ‘You are Rena Dourou?’ ”

In the end, she won 50.8 percent of the vote, shocking the political establishment here.

Born in Athens to a police officer and a stay-at-home mother, she says that in the ordinary course of things, she would have taken her place in the broad ranks of the civil service here. But her parents spent heavily on their children’s education, making sure they had everything from ballet to language lessons. She speaks five languages, including Turkish.

Eventually, she ended up with a scholarship to Essex University in Britain, where her professors encouraged her to pursue a Ph.D., she said. But she settled for a master’s degree in political science, eager to return home and go into politics. Over the years, she has held jobs in advertising and publishing, all the while spending nights and weekends devoted to Syriza. She won election to Parliament in 2012, and was the party’s point person on international affairs.

She says she would like to have children but, for now, has her hands full. “I don’t want to just dump the kid on my mom to raise,” she said.

As Ms. Dourou settles into office, she says her goal is simple: creating an open, functional government without the corruption and back-room deals that have been a way of life in this country. “At the end of five years,” she said, “the government of Attica will be like a government in other countries.”

But for the time being, she remains an official with few allies in office and little experience. A few months after winning and before taking office, she sent a formal letter to her predecessor asking to be briefed on the “loose ends” and “current issues” in the region. In his response, he told her the information was on “corresponding websites.”

Asked what her budget is, she admits that she is waiting for a Monday morning briefing from her staff to really get a handle on it. (Official statistics indicate that last year’s was about $480 million.)

Nonetheless, she has already made headlines for a public brawl with the central government over the future of thousands of municipal workers in her region. The central government wants to review their credentials and evaluate their performance. But Ms. Dourou sees this as a thinly veiled starting point for cutting workers and pleasing Greece’s creditors, and she is refusing to hand over their files.

In a recent speech, she said that there would be zero tolerance for workers who lied about their credentials. But ferreting them out was her business. In her office, she said she had already begun proceedings against eight employees, cases that had been pending on her predecessor’s desk.

“Employees are going to have a harder time,” Ms. Dourou said. “You have to be strict to get anything done. But I will do it my way.” Her stance has prompted criticism, including from a columnist who called her the “Duchess of Athens,” saying she has grown arrogant overnight.

Even before the elections, Ms. Dourou, 39, had gained a reputation for toughness, at least in part for her performance during a live television show discussing election issues. As the discussion got heated, a member of Golden Dawn threw a glass of water in her face. She barely flinched.

The show ended in a brawl between the right-wing candidate and another female politician. But Ms. Dourou never lost her composure, a scene that thousands of Greeks watched on YouTube. While she waited to take office, she said, nobody approached her about anything. “They don’t have the guts,” she said laughing. “But they will come.”

Still, politics in patriarchal Greece can be tough on women. Last year, the vice president of the government, Evangelos Venizelos, told a female member of Parliament that “she should be pregnant.”

As Ms. Dourou was campaigning for office, a former deputy prime minister from the socialist Pasok Party, Theodoros Pangalos, said in a radio interview that he could not stand seeing posters of Ms. Dourou’s “filthy face” all over Athens. He added that he would “like to see her campaign complete with a full-body picture of her with a bikini.”

In a ponytail and jeans, and at work long after business hours recently, Ms. Dourou simply sighs at the state of sexism in her country. Ms. Dourou is in a civil union with a businessman, Giannis Benisis, instead of a marriage because “it doesn’t have the limitations that a marriage does, most notably in case of a breakup, you don’t need lawyers and you don’t have to go through situations that might kill everything nice that you’ve experienced with your partner.”

She said she could have waited for the next national elections with the expectation of becoming a minister, but she wanted to run something. Though it is rarely done, she resigned from her seat in Parliament to campaign rather than get paid for a job she was no longer doing.

It left her without a salary for more than seven months, and unable to pay her staff. “My mother is paying for my cigarettes,” she said this summer, as she waited three months in a borrowed office. “These people you see here are working for nothing. So there is hope for my country.”

Correction:

The Saturday Profile article last week, about Rena Dourou, a Greek politician whose election as the new prefect of Athens was the most significant victory so far of the left-wing Syriza Party, misspelled the surname of Ms. Dourou’s partner. He is Giannis Benisis, not Benisi.

A version of this article appears in print on , on Page A10 of the New York edition with the headline: A Greek Politician Willing to Face the People. Order Reprints | Today’s Paper | Subscribe

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